Combo Sump with Turf Scrubber, DSB & Fuge

I've started to build a sump out of a 29 gallon tank I had laying about.
I started by sectioning off 4 inch compartments for the intake and return,
leaving 19 inches in the middle. But instead of using it all for a chaeto
refugium I decided to add a special sixth baffle about 1/3 of the way to
provide some more features.





What this sixth baffle does..

* The baffle partitions off a 6-inch deep, 2-gallon volume deep sandbed.

* Baffle is submerged to allow the top 2 inches of water to circulate over both the sandbed and refugium, with a barrier to screen out chaeto.

* Baffle has two vertical extensions to hold the bottom of a 10x12 inch algae turf scrubber screen which slopes down to it at a steep angle.


Sixth baffle in its future location. Blue line on sump is fuge water level.


Sixth baffle holding the sandbed. Chaeto barrier is not shown.



With this sheltered DSB I am counting on nitrates diffusing back over
from the fuge, since water flowing over the turf screen bypasses the
sandbed for the most part. Suspended detritis flows into the 8 inch
deep refugium instead of onto the sandbed, helping to keep it clean.


Sixth baffle also showing ATS screen holder location.



Lighting

I plan to hang two 27 watt 6500K helical CF lights up to 3.5" below
the rim, aimed directly at the ATS screen with the fuge getting its
light off of the sides of the bulbs. Even with the lights hanging this
low the sump still has 8 gallons of reserve to handle power outages.


Filtration capacity


* With a 12x10 inch screen the sump would provide just over
half the recommended ATS filtration capacity for a 100 gallon
system due to its single sided screen.


* The sump provides about half of the most often cited DSB
volume to support a 100 gallon system (citing Anthony Calfo).


* The shallow refugium holds roughly half the chaeto you'd
want to grow to support a 100 gallon display tank.


After running for about a month the combo sump should reach its
nominal capacity, mainly reducing nitrates. As the sump continues
to mature over the next couple months, the ATS will come online
and begin scrubbing the water of phospates and metals, while it
raises the pH and lowers nitrates even further (citing Santa Monica
of algaescrubber.com).

Due to the sump's triple redundancy in nutrient removal, if chaeto
is overpruned or allowed to grow too dense the DSB and ATS can
make up for the resulting loss of productivity. Likewise, the DSB
and the chaeto sections can take up the slack during periods of
low ATS productivity. Such periods can result from overscraping a
screen or, more often, from neglecting to scrape the screen weekly.

This sump therefore has the potential to reduce ATS maintenance
as the system can adapt well to a less frequent scraping regimen.
I'll post more pictures when I complete the sixth baffle and finalize
its location. Here is a spreadsheet view showing all the dimensions.
Reserve capacities and the maximum ATS screen size are calculated.

I welcome all comments and suggestions as this comes together!

 

looks like a good idea just how are the going to baffle the noise of the water runing of the turf scrubber

also you need to remove the turf sheet every week and clean it how are you going to go this

 

The ATS screen sits with its top edge leaning against
a baffle and the bottom edge sitting on a ledge glued
to the sixth baffle. There will be a narrow glass strip
in the center to keep the screen from bowing too much.
It'll be a snap to pull it out, scrape it, and put back in.
I will be posting a new picture of the 6th baffle soon.

How much noise I'll get is a big mystery for me so far.
There is a vertical drop of about 7.75 inches and if the
screen were not present it'd sound like Niagara Falls!

With the screen in place, some design aspects should
help to minimize noise. The screen extends 12 inches
from edge to edge to hopefully capture all the water
flowing over the tallest baffle. My guess is that if any
water does leak around the edges it will quietly flow
down along down the walls.

As for water falling through the screen, I tested the
screen material a couple days ago and when water is
flowing across the screen at a steep angle it doesn't
seem to seep through at all. My guess is not much
will drip down from the screen- but I'll soon find out!

 

Sounds like a lot of thought went into this plan. I like the idea of a sheltered DSB and use of algae scrubber. I look forward to seeing results. Is your skimmer housed somewhere else?

 

Thanks I will update the pictures after more silicone
has a chance to dry. The skimmer will be either a
Prizm Deluxe or a modded CPR BakPak 2R+ hang on.
It would sit off the side of the intake compartment.

 

More progress..

Some more progress on the sump construction to show.

Another view of the sixth baffle. I made this out of the
glass scraps left over after Lowe's cut my first 5 baffles
and you can see the horizontal seam where they were
siliconed together, reinforced by the two vertical cross
pieces.




The ATS screen holder is siliconed onto the cross pieces. It is
made from a piece of black plastic that used to be part of an
old videocassette rack. I dremeled the sides a bit to open up
a slot so the screen can sit inside it for extra stability, and to
channel the water flow a bit. The upstream edge of the holder
tips up slightly though this is kind of hard to see from the pic.




Side view of the sixth baffle with ATS screen holder. Having a
slot running the length is useful but probably not necessary.


Siliconing the sixth baffle into place.


Black eggcrate siliconed to the gap under the screen holder.
This is a barrier for keeping chaeto out of the sandbed zone.


One more scrap left over from Lowe's may make a good
center brace for the ATS screen, to keep it from sagging.
The blue line marks where I'll need to have it cut to size.
If the screen drips too much this narrow brace may have
to be replaced with a full-width pane of glass to channel
100% of the flow onto the ATS screen.


More to come.......

 

Looking good.

 

Return Section

For an algae turf scrubber the rule of thumb for water flow
is 35 gph per inch of screen width. For my 12" ATS screen
that's 415 gph. I obtained a used Rio+ 2100 for my return,
which outputs 692 gph with 0' head, and 375 gph with a 4'
head, so there will be enough flow moving through the sump.
A braided 3/4" hose, a section of which is visible below, will
connect the pump to a Loc-Line return spout mounted over
the display tank.

I also wanted the option to divert some flow back into the
return compartment so I added a tee with a ball valve and
a PVC elbow to direct the diverted flow downward. I will
use this flow to create some turbulance in an area where
I plan to put bags of carbon pellets and, at least initially,
ROWAphos. This will improve water flow through the media
in part by keeping the bag in motion; like dunking a teabag.

Return pump output fitted with braided hose, tee, 1/2" ball
valve & elbow downspout. Hose to display tank not shown.



On Thursday I cut a piece of black eggcrate to set the
pump on top of, and then made a cage-like contraption
using zip ties to contain a media bag suspended about
an inch above the bottom. The cage has a hinged lid to
keep the bag from floating off or being washed into the
intake.

The completed return platform - with media cage door open



Yesterday I decided this cage was too small, so I rebuilt it.
I doubled the size so it holds two media bags instead of one.


Return platform with expanded media cage, and Rio pump

 

nice! i have the same setup (ats/refugium combo). my problem is this...i have a 265 gall reef and i dont know what size tank i should use for an ats/refugium. the one i have now is way small. i calculated volume based on size and the hole for the return (all gravity, no pumps) and discovered only 8 gallons are in the ref/ats at any given time. do i get a 30 gallon tank or what? plus, i like ur design. i want to do something similar. hit me back if u get a chance!

 

For your large display tank, consider making your sump out of a tank sized 55-90 gallons. At this point I would also start shopping for a return pump! Like you, I have an elevated ATS that has been a real pain to pull down from the shelf for bi-weekly service, and I'm looking forward to the convenience of having my turf screen in the sump. This design makes it super easy to pull out, scrape, rinse and return the turf screen - in about 5 minutes.

It's true that having an ATS in the combo sump sacrifices refugium volume. For instance, my 29 gallon combo holds only 12 gallons because of the 7.75 inch vertical dropoff needed for the ATS. But this is not a bad thing if growing chaeto is the purpose of the refugium. Compared with a deep fuge, a shallow fuge needs less light to penetrate a shallower water column, which translates to a higher growth rate per watt.

Having a lower operational level also gives the sump more room to contain the overflow from your large display tank during power outages. In turn, this extra headroom allows you to safely suspend your daylight bulbs well below the tank rim - putting them right next to the ATS screen where you want 'em.